Azo dyestuffs containing thiosulfatoarylpyrazolone groups



United States Patent 1C6 Patented f fi fig 2 I is the radical of a diazo compound connected to the O Y STUFFS cgfiN gfi NG T SULFATO adjoining C of the pyrazolone by an azo group of said AIN radical, said radical having an aromatic portion bearing ARYLPYRAZOLONE GROUPS two metallizable substituents ortho to each other; and in Maryland tached to the benzene nucleus.

No Drawing. Filed Apr. 11, 1966, Ser. No. 541,514 14 Claims. (Cl. 260145) This is a continuation-in-part of my copending United States patent application Serial No. 383,259, filed July ABSTRACT OF THE DISCLOSURE 16, 1964, and now abandoned, and the benefit of said There are disclosed herein azo dyestuffs of the group filing date f v The present invention relates to dyestuffs, and more Y particularly to azo dyestuffs and method for making same. 15 Generally speaking, the azo dyestuffs of the present invention are particularly characterized in that they are dyestuffs selected from the group consisting of: XC=N SSO Z a 1:1 and 1:2 metal complexes of 0H 0H Y Y RC=C N y X C=N sso z X-C=N SSO3Z OH OH Y I Y C=C--N=N--DD-N=N-C=C I N\ N. Z0335 N=C-X XC=N/ SSOaZ 1.1 1 1 f (c) 1:1 copper, 1:1 cobalt, 1:1 chromium, 1:1 nickel, 1:1 meta Comp exes 0 iron, 1:2 chromium, 1:2 cobalt, or 1:2 nickel complex 0H 7 compounds of an azo dye of the formula J1C=(]) Y OH N- I-C=C X-C=N sso z X-C=N SSOaZ OH OH and the metal complex compound resulting f 1 (d) 1:1 copper, 1:1 cobalt, 1:1 chromium, 1:1 nickel, or

mucous reaction f 1 molecular proportion f 1:1 iron complex compounds of an azo dye of the formula CH3 OH Y I Y /N=C J C=C\ I I N ZOaSS (l7=G-N=N SO2NHOH3 X-C=N SSOaZ OH (e) The metal complex compound resulting from simul- OH 2 taneous reaction of 1 molecular proportion of an azo 2 molecular proportions of dyestutf of the formula 1 Y y CH3 JO=C l l I SSOQZ 3 8 C=CN=N@SOzNHCHz-- and 2 atomic proportions of Co, Cr or Ni; wherein R is 6 I J the radical of a diazo compound connected to the C of 0H 2 the pyrazolone by an azo group of said radical; X is the 2 molecular proportions of gamma portion of an alpha unsubstituted beta keto ac1d or ester; Y is H, halogen, lower alkyl, lower alkoxy or Y the radical of a sultonamide; Z is H, Na, K or NH D is J-C=O an arylene group; J is the radical of a diazo compound having a metallizable substituent on an aromatic portion thereof, a ring C atom of which aromatic portion is linked 7O X C=N S8032 to the C of the pyrazolone via an azo group of said radical, and 2 atomic proportions of Co, Cr, or Ni, said reactants and the metallizable substituent is ortho to said azo group; being in solution; wherein R is the radical of a diazo compound connected to the adjoining carbon of the pyrazolone ring by an azo group of said radical of the diazo compound;

X is the gamma portion of an alpha unsubstituted beta keto ester or the gamma portion of an alpha unsubstituted beta keto acid;

Y is hydrogen, halogen, lower alkyl, lower alkoxy, or the radical of a sulfonamide;

Z is H, Na, K, or NH.,;

D is an arylene group;

J is the radical of a diazo compound having a metallizable substituent on an aromatic portion thereof, a ring C atom of which aromatic portion is linked to the C atom of the pyrazolone ring via an azo group of the radical of the diazo compound, and in which the metallizable substituent is located ortho to said azo group;

to form an azo dyestufr of the formula OH OH I is the radical of a diazo compound connected to the adjoining carbon of the pyrazolone ring by an azo group of said radical of the diazo compound, said radical of the diazo compound being further characterized in having an aromatic portion bearing two metallizable substituents ortho to each other;

and in which the SSO Z group is located meta or para with respect to the N attached to the benzene nucleus.

Generally speaking, the method of the present invention is a method for synthesizing an azo dyestuff comprising the step of coupling equimolar proportions of a diazo compound and a pyrazolone compound of the formula wherein X is the gamma portion of an alpha unsubstituted beta keto ester or the gamma portion of an alpha unsubstituted beta keto acid; Y is hydrogen, halogen, lower alkyl, lower alkoxy, or the radical of a sulfonamide; Z is H, Na, K, or NR and the SSG Z group is positioned meta or para with respect to the N attached to the benzene nucleus.

If desired, a diazo compound may be utilized which has a metallizable substituent on the aromatic portion thereof which aromatic portion is attached to the terminal azo group, said metallizable substituent being positioned ortho with respect to said terminal azo group. As used herein, the term terminal azo group refers to the azo group formed from the amine when a diazotizable aromatic amine is diazotized. When a diazo compound having such metallizable substituent is utilized, the method of the present invention may also comprise reacting a molecular proportion of a solution of the resulting dyestuff with an atomic proportion of copper, cobalt, chromium, nickel or iron, or with 0.5 atomic proportions of chromium, cobalt or nickel to form a metal complex of the azo dyestuff, said metal being an aqueous solution of its salt and said reaction being conducted at an elevated temperature. When 1 atomic proportion of the metal and 1 molecular proportion of the dye are used, a 1:1 metal complex of the azo dye results; and when 0.5 atomic proportion of the metal and 1 molecular proportion of the dye are used, the 1:2 metal complex of the azo dye results.

Alternatively, a diazo compound may be utilized in which an aromatic portion of said diazo compound has two metallizable substituents located ortho to each other, in which case a molecular proportion of the resulting dyestutf may be reacted with an atomic proportion of copper, cobalt, chromium, nickel or iron, said metal being an aqueous solution of its salt, said reactants being in wherein D is an aryl group, such as a radical of the phenylene or naphthylene series, and X, Y, Z and the position of SSO Z are as above defined.

The pyrazolone compounds, or dye intermediates, used in making the dyes of the present invention may be represented by the general formula wherein X is the gamma portion of an alpha unsubstituted beta keto ester or the gamma portion of an alpha unsubstituted beta keto acid; Y is hydrogen, halogen, lower alkyl, lower alkoxy, or the radical of a sulfonamide; Z is H, Na, K, or NH and the S80 2 group is positioned meta or para with respect to the N attached to the benzene nucleus. These compounds are disclosed and claimed in my copending US. patent application Serial No. 541,498, filed on even date herewith.

Generally speaking, these pyrazolone compounds may be prepared by a process comprising the steps of diazotizing an amine of the formula wherein Y and Z are as above defined and the S80 2 group is meta or para with respect to the N attached to p the benzene nucleus; reacting the resulting diazonium compound with an alkali metal sulfite to form an alkali metal phenylhydrazinesulfonate; acidifying the resulting sulfonate at 035 C. with a strong mineral acid to form a hydrazine; and condensing equimolar proportions of the hydrazine and an alpha unsubstituted beta keto ester or an alpha unsubstituted beta. keto acid to form a pyrazolone by ring closure.

It is quite surprising and unexpected that the pyrazolone compounds used in the present invention may be synthesized, as one with skill in the art would expect that the notoriously labile SSO Z group of the amine would not remain stable throughout the process, but would decompose, such as by splitting ofl? an SO Z group and form ing a mercapto amine, and enter into undesirable side reactions. In fact, the reaction does not proceed, and a tarry residue results, if acidification to form the hydrazine is conducted at a temperature above 35 C. Moreover, if one attempts to diazotize orthoaminothiophenylthiosulfates, the thiosulfate group enters into undesirable side reactions, rendering the process valueless.

A more detailed description for preparing the pyrazolone intermediate follows.

A molecular proportion of an amine of the formula SSOaZ wherein Y and Z are as above defined and the SSO Z group is meta or para with respect to the N attached to the benzene nucleus, is diazotized by conventional diazotization technique, such as by dissolving the amine in water, cooling to 0 C., acidifying with HCl, and adding NaNO at 0-10 C. as consumed. The corresponding diazonium salt results.

The resulting diazonium salt is reacted with a molecular proportion of an alkali metal sulfite, such as sodium sulfite, potassium sulfite, or caustic plus a bisulfite which react to form the alkali metal sulfite, to produce the corresponding alkali metal phenylhydrazinesulfonate. This reaction may be effected by stirring an aqueous solution of the above diazonium salt with the alkali metal sulfite at 015 C. for 3-10 hours.

The resulting alkali metal phenylhydnazinesulfonate is then converted to the corresponding hydrazine by acidifying with a strong mineral acid, such as H 80 HCl, and H PO and preferably H 80 for reasons of economy, and maintaining at 0-35 C. for 12-48 hours; reaction is complete when the S0 is liberated. Temperature control in the acidification step is important, as excessive heat causes decomposition.

The resulting hydrazine is then condensed with a molecular proportion of an alpha unsubstituted beta keto ester or alpha unsubstituted beta keto acid. This condensation may be effected by stirring the reactants at 1535 C. for 8-48 hours.

Alpha unsubstituted beta keto esters have the formula R -COCH -COOR The R is the gamma portion of the ester; the CO is the beta portion of the ester; the CH is the alpha portion of the ester; the term alpha unsubstituted refers to the fact that the hydrogens of the CH are unsubstituted; and the COOR is the carboalkoxy portion of the ester. In these alpha unsubstituted beta keto esters, R is an alkyl group and R may be carboalkoxy, alkyl, aryl, hydrogen or furyl. Alpha unsubstituted beta keto acids are analagous, except that R is H, and except that R may also be carboxy.

As a result of the above condensation of the hydrazine and the alpha unsubstituted beta keto ester or acid, the R substituent and the adjacent oxygen are split out, along with the amino hydrogens of the hydrazine, to form an R OH alcohol and water in the case of theester, and water in the case of acid, thereby permitting-ring closure of the hydrazine and ester or acid, in which the R of the ester or acid becomes the X of the pyrazolone compound,

SSO H wherein X and Y are as above defined and the SSO H group is meta or para to the N attached to the benzene ring.

The above thiosulfuric acid form may be converted to the corresponding thiosulfate salt form (SSO Na, or SSO K, or SSO NH by reacting the acid with an alkali salt of Na, K, or NH and the resulting thiosulfate salt may be isolated by evaporating to dryness or salting out.

Non-limiting examples of X in the pyrazolone intermediates and in the compounds of the present invention are hydrogen; a radical of the benzene series, such as phenyl, chlorophenyl, methoxyphenyl, ethoxyphenyl, nitrophenyl and tolyl; naphthyl; furyl; lower alkoxy carbonyl, such as methoxycarbonyl or ethoxyca-rbonyl; carboxy; and lower alkyl, such as methyl, ethyl, propyl and isopropyl. Alpha unsubstituted beta keto acids, in which the gamma portion is identical to X, or alpha unsubstituted beta keto esters, in which the gamma portion is identical to X except for carboxy, may be used in the present process.

Example 1 The pyrazolone compound of the formula may be prepared as follows.

1 g.m.w. (227 gms.) sodium S-4-aminophenylt-hiosulfate is diazotized by dissolving in 1,000 ml. H O at 35 C., cooling to 0 C., adding 225 gms. 20 B. HCl, and adding 69 gms. NaNO as consumed. The diazonium salt of sodium S-4-aminophenylthiosulfate results.

A solution of sodium sulfite is prepared by slurrying 230 gms. sodium bisulfite in 500 gms. ice, adding 100 ml. 50% aqueous NaOH, and stirring until the pH adjusts to 7.0. The above resulting diazonium salt of sodium S-4- aminophenylthiosulfate is added to the solution of sodium sulfite gradually during a period of one hour, while maintaining the'temperature at 0 C. and the pH at 7.0- 7.2 by adding sodium bisulfite or NaOH as needed. The resulting mixture is permitted to stand 1218 hours, forming a yellowish solution of (sodium 4-S-sodiothiosulfatophenylhydrazinesulfonate) To the above solution of sodium 4-S-so'diothiosulfatophenylhydrazinesulfonate is added, at 2025 CI, 500 gms. 98% H 80 and the mixture is stirred until all S0 is liberated, e.g. 20 hours at 20-30 C. or 48 hours at 0-10 C., forming Bowen-@ssonr (4-thiosulfatophenylhydrazine) A slight excess over 1 g.m.w. ethyl acetoacetate is added to the hydrazine, and the mixture stirred 20 hours at 25 30 C. The resulting solids product is collected by filtration, washed with ice water, and air dried.

In the examples given in the following table, the procedure is the same as that given in Example 1 above, and the examples in the table indicate that a molecular proportion of the thiosulfate salt in the second column is diazotized, the resulting diazo reacted with sodium sulfite and the result acidified to form a hydrazine, and the hydrazine reacted with a molecular proportion of the alpha unsubstituted beta keto ester or acid in the third column to form the pyrazolone compound in the fourth column.

1151x. Thiosulfate Salt Ester or Acid Pyrazolone 25. Sodium S-4arninophenylthiosulfate n Isobutyrylacetic acid (|)H HO==C GE: /N- SSOSH C HO=N C H:

26. Sodium S-3aminophenylthiosuliate p-Nitrobenzoylacetic acid ()H HC=C N OzN G=N SS 3H The products of the above examples are in the thiosulfuric acid form. These acids may be easily converted to their salts by dissolving them in water, reacting with an equivalent amount of an alkali of Na, K, or NH, (such as NaOH, Na CO KOH, K CO NH OH, etc.) and evaporating to dryness, in which case the corresponding Na, K or NH; ion of the alkali replaces the H atom of the thiosulfuric acid. An illustrative example follows.

Example 27 The compound of the formula may be prepared by dispersing l g.m.w. of the product of Example 1 in 1,000 ml. water at 0., adding thereto 0.5 g.m.w. of Na CO in aqueous form, stirring, evaporating the resulting salt solution to dryness, and collecting the solids product.

I Y R-C=C\ l XC=N sso z may be prepared by a process comprising the step of coupling equimolar proportions of a diazo compound with a pyrazolone compound of the formula XC=N wherein R is the radical of a diazo compound connected to the adjoining carbon of the pyrazolone ring by an azo group of said diazo compound; X is gamma portion of an alpha unsubstituted beta keto ester or the gamma portion of an alpha unsubstituted beta keto acid; Y is hydrogen, halogen, lower alkyl, lower alkoxy, or the radical of a sulfonamide; Z is H, Na, K, or NH.;; and the SSO Z group is positioned meta or para with respect to the N attached to the benzene nucleus. Illustrative exam ples of X in the above dye and in the other dyes of the present invention are hydrogen; furyl; carboalkoxy, such as lower al'koxy carbonyl, methoxycarbonyl, and ethoxycarbonyl; alkyl, such as lower alkyl, methyl, ethyl, and isopropyl; aryl, such as naphthyl, a radical of the benzene series, phenyl, chlorophenyl, methoxyphenyl, ethoxyphenyl, nitrophenyl and tolyl; and carboxy.

The pyrazolone intermediates may be in either the thiosulfuric acid (SSO H) form or the thiosulfate salt (SSO Na, $50 K, or SSO NH form when coupled with the diazonium salt, and the coupling may be under alkaline, neutral or acid aqueous conditions, although preferably under alkaline. The coupling may be effected by adding an alkali or acid binding agent to the pyrazolone intermediate to bind the free acid, rendering aqueous, and adding thereto a diazonium salt solution; the azo dyestuif results as a solution of the thiosulfate salt, and may be recovered as thiosulfate salt solid by evaporating to dryness or by salting out, or the dye may be recovered as the thiosulfuric acid by rendering the solution slightly acid and collecting the resulting precipitate. The coupling reaction may be conducted at about 020 C., preferably commencing the coupling at about 5 C. and allowing the mass to warm to room temperature during the reaction.

Diazo compounds, with which the pyrazolone intermediates are coupled, are well known. They are prepared by diazotizing a diazotizable aromatic amine (azoic base), many of which diazotizable aromatic amines are listed by common name, chemical name, and structural formula in Lubs, The Chemistry of Synthetic Dyes and Pigments, pp. 196-207, 1955 ed., Reinhold Publishing Corp., New York, NY.

The diazo compounds may be devoid of metallizable substituents, or they may have a metallizable substituent on an aromatic portion thereof which metallizable substituent is located ortho to the terminal azo group, or they may have two metallizable substituents on an aromatic portion of the diazo compound which metallizable substituents are located ortho to each other. In that case, the azo dyes may be converted into their metal complex compounds. Illustrative examples of suitable metallizable groups are OH, COOH, and OCH COOH.

Valuable azo dyestuffs of the formula may be prepared by diazotizin-g an amine 0f the formula 13 and coupling equimolar amounts of the resulting diazo com-pound and a pyrazolone compound of the formula wherein R is hydrogen, halogen, lower alkyl, lower alkoxy, or p'henoxy; E is a radical of the phenylene or naphthylene series; and X, Y, Z and the position of 880 2 are as above defined.

Azo dyes of the formula wherein I, X, Y, Z and the position of the SSO Z group are as above defined may be prepared by coupling equimolar proportions of a pyrazolone intermediate of the formula and a diazo compound having a meta'llizable substituent, such as OH, COOH or OCH COOH, on the aromatic portion thereof which aromatic portion is attached to the terminal azo group, said metallizable substituent being positioned ortho with respect to said terminal azo .group. 1:1 copper, 1:1 cobalt, 1:1 chromium, 1:1 nickel, or 1:1

iron complex compounds of these azo dyes of the formula wherein J X, Y, Z, and the position of the SSO Z group are as above defined, may be prepared by coupling equimolar proportions of a pyrazolone intermediate of the formula and a diazo compound in which an aromatic portion of the diazo compound has two metallizable substituents located ortho to each other. 1:1 copper, 1:1 cobalt, 1:1 chromium, 1:1 nickel or 1:1 iron complex compounds of thees azo dyes may be prepared by heating an aqueous composition of a molecular proportion of the dye with an atomic proportion of an aqueous solution of Cu, Cr, Co, Ni, or Fe, said metals being a solution of their soluble salts.

An azo dye of the formula may be prepared by diazotizing an amine of the formula Nnsor may be prepared by heating an aqueous composition of J 1 and coupling equimolar proportions of the resulting diazo compound and a pyrazolone compound of the formula wherein R is a metallizable group such as OH, COOH or OCH COOH in ortho position to the azo of the dye or to the NH in the case of the amine; R is in para or meta position to the azo group of the dye or to the NH in the case of the amine and is hydrogen, halogen, lower alkyl, or lower alkoxy; the NI-ISO; group is located meta or para to the azo group of the dye or to the NH in the case ofthe amine; and R X, Y, Z, and the position of the SSO Z group are as above defined. 1:1 copper, 1:1 cobalt, 1:1 chromium, 1:1 nickel, or 1:1 iron complex compounds of these azo dyes may be prepared by heating an aqueous composition of a molecular proportion of the dye with an atomic proportion of an aqueous solution of Cu, Cr, Co, Ni or Fe, said metals being a solution of their soluble salts. The 1:2 chromium, 1:2 cobalt, or 1:2 nickel complex compounds of these azo dyes may be prepared in similar manner except that 0.5 atomic proportion of the metal is employed.

Metal complex compounds of azo dyes may also be prepared by heating an aqueous composition comprising 1 molecular proportion of an azo dyestuff of the formula soz rroHz 2 molecular proportions of and 2 atomic proportions of an aqueous solution of Co, Cr, or Ni, said metals being a solution of their soluble salts, and the reactants being in solution when they react; wherein I, X, Y, Z and the position of the SSO Z group are as above defined.

which is used in the above reaction may be prepared by tetrazotizing a molecular proportion of l OH on (4,4' diamino 3,3-dihydroxy-ethylene disulfonamide), and coupling the resulting tetrazo compound with 2 molecular proportions of Example 28 The azo dyestuff of the formula GH;C=N may be prepared as follows.

1 g.m.w. of 3-chloroaniline is diazotized in known manner by adding 1 g.m.w. of 3-chloroaniline to 2,500 ml. water at 25 C., adding thereto 225 gms. concentrated HCl at room temperature with stirring, heating the mixture to C. and stirring until solution results, cooling the solution to 0 C. and holding at that temperature while a slight excess of NaNO as shown on starch-KI paper, is added thereto with stirring. A solution of diazotized 3-chloroaniline results.

Equimolar proportions of the diazotized 3-chloroaniline and pyrazolone compound are coupled as follows. 1 g.m.w. of the pyrazolone compound of Example 1 and '600 ml. 20% aqueous Na CO are dissolved in 2,500 ml. water at 25 C., to which is added 350 gms. NaHCO and the mixture cooled to 0 C. While maintaining the solution of pyrazolone compound at 0 C., add thereto gradually, during a period of one hour, with stirring, the above solution of diazotized S-chloroaniline at 0 C. Stir for 12 hours, allowing the temperature to rise to 20 C., and recover the resulting solids. The product is yellow dye in the form of the sodium thiosulfate salt.

If the potassium thiosulfate salt of the above dye is desired, equivalent amounts of K CO and KHCO may be substituted for the Na CO and NaHCO and if the ammonium thiosulfate salt is desired, equivalent amounts of NH OH and NH HCO may be substituted.

The thiosulfate salt may be converted to the thiosulfuric acid by dissolving in water, rendering slightly acid with HCl at room temperature and collecting the resulting precipitate by filtration.

Examples 29-43M In the examples given in the following table, the procedure is the same as that given in Example 2 8, and the examples indicate that a molecular proportion of the diazotizable amine shown in the second column is diazotized and coupled with a molecular proportion of the pyrazolone compound shown in the third column to produce the azo dyestuif shown in the fourth column, which has the shade given in the fifth column. The chemical names and structural formulas for those diazotizable amines which are listed by their common names in the table are given in Lubs, The Chemistry of Synthetic Dyes and Pigments, pp. 196-207, 1955 ed., Reinhold Publishing Corp., New York, NY.

The following examples are illustrative of premetallizing azo dyes of the present invention.

Example 44 The azo dye of the formula may be prepared as follows.

1 g.m.w. of diazotized 4-chloro-2-aminophenol is coupled to 1 g.m.w. of the product of Example 27 to form a non-metallized dyestufi of the formula which is added to liters of water and heated to 80 C. To it is added a copper sulphate solution which has been prepared by dissolving 249.71 grns. copper sulphate pentahydrate in 3 liters of water at 90 C., cooling to C., and redissolving with 1,000 gms. 28% aqueous ammonia. The result is heated at 80 C. for 2 hours, and the tan metallized dyestutf separates on salting with NaCl.

Example The azo dye of the formula may be prepared as follows.

1 g.m.w. of the non-metallized dyestuff of Example 44 above is added to 10 liters water, and heated to 80 C. To it are added 281.1 gms. CoSO -7H O dissolved in 3 liters water, and the result heated to 80 C. for 2 hours. The tan metallized dyestuif separates on salting with NaCl.

Example 46 The azo dye of the formula N@-ssoma may be prepared as follows.

1 g.m.w. of the non-metallized dyestuff of Example 44 is added to 10 liters water at 60 C. To it are added 594 gms. of a aqueous solution of chromium acetate monohydrate; and the composition is heated at 80 C. for 2 hours while maintaining pH 7. The red metallized dyestufi' separates on salting with NaCl.

28 Example 47 The azo dye of the formula CHa-G=N may be prepared as follows.

1 g.m.w. of diazotized o-aminobenzoic acid is coupled with l g.m.w. of the product of Example 27 to form a non-metallized azo dye of the formula.

COONa CH3C=N and 1 g.m.w. thereof is added to 10 liters water and heated to C. To it are added 262.85 gms. NiSO -6H O dissolved in 3 liters water. The composition is heated at 80 C. for 2 hours. The yellow metallized dyestutf separates on salting with NaCl.

Example 48 The azo dye of the formula CHa-C=N may be prepared as follows.

1 g.m.w. of the non-metallized dye of Example 47 above is added to 10 liters water and heated to 60 C. To it is added 594.32 gms. of a 50% aqueous solution of chromium acetate monohydrate. The composition is heated at 80 C. for 2 hours. The yellow metallized dyestuff separates on salting with NaCl.

Example 49 The azo dye of the formula 29 The 1:2 nickel complex analog of the above dye may be prepared by substituting 131.42 gms. NiSO -6H O dissolved in 1.5 liters water for the chromium acetate solution used above.

Example 50 The azo dye of the formula SOPNHi on.

may be prepared as follows.

1 g.m.w. of diazotized 2-aminophenol-4-sulfonamide is coupled with 1 g.m.w. of the product of Example 27 to produce a non-metallized dyestuff of the formula 1 g.m.w. of this dyestuff is premetallized by adding thereto liters water and also 162.21 gms. FeCl dissolved in 3 liters water; heating to 80 C.; and holding at 80 C. for 2 hours while maintaining pH 7 by adding caustic soda as needed The resulting olive dyestufI separates on salting with NaCl.

Example 50A The azo dye of the formula N@ SSO.N.

' I SOzNHz CH3 may be prepared as follows.

This example is the same as Example 50 above, except that 1 g.n1.w. of the non-metallized dyestuif of Example 50 is premetallized by adding to 10 liters water, heating to 60 C., adding thereto 594.32 gms. of a 50% aqueous solution of chromium acetate monohydrate, and heating at 80 C. for 2 hours. The orange metallized dyestufi separates on salting with NaCl.

Example 50B The azo dye of the formula may be prepared as follows.

1 g.m.w. of diazotized and the pyrazolone intermediate of Example 27 above, both in aqueous solution, are coupled at 510 C.

The resulting dye is adjusted to 10 liters aqueous volume, 594.32 grns. of a 50% aqueous solution of chromium acetate monohydrate is added, the pH adjusted to 6.5 with acetic acid, the mixture heated to C., and heating is continued at 85 90 C. for 4 hours, while the pH is maintained at 6.4-6.7. The orange meta-lh'zed dyestufi" precipitates on salting with NaCl.

Example 51 The azo dye of the formula Ni O\ N=NC=O I C2H5C=N SSOsK may be prepared as follows.

1 g.m.w. of diazotized o-aminobenzoic acid is coupled with 1 g.m.w. of

in the manner described in Example 47 above. The yellow metallized dyestulf results on evaporating to dryness.

Example 52 The azo dye of the formula may be prepared as follows.

1 g.m.w. of diazotized Z-aminophenol is coupled to 1 g.m.w. of

to form a non-metallized dyestuff of the formula and 1 g.m.w. thereof is reacted with 594 gms. of a 50% solution of chromium acetate in the manner described in Example 48 above. The orange metallized dyestuff results on evaporating to dryness.

3 1 Example 53 The azo dye of the formula may be prepared as follows.

1 g.m.w. of diazotized o-aminobenzoic acid is coupled with 1 g.m.w.

-C=N l SSOaNa and the result rendered slightly acid with HCl at 25 C., to precipitate a non-metallized dye of the formula may be prepared as follows.

1 g.m.w. of diazotized 2-aminophenoxyacetic acid is coupled with 1 g.m.w. of

I SO NH HC=C CH -C N to form the non-metallized dye of the formula OCHz-COONa N @-ssoma and 1 g.m.w. thereof is reacted with 594 grns. of 50% chromium acetate monohydrate in the manner described in Example 48. The yellow metallized dyestutf separates on salting with NaCl.

32 Example 55 The azo dye of the formula may be prepared as follows.

This example is the same as Example 45 above, except that 1 g.m.w. of

is substituted for the non rnetallized dyestutf used in Example 45.

The resulting metallized dye is orange.

Example 56 The azo dye of the formula may be prepared as follows.

This example is the same as Example 46 above, ex-

is substituted for the non-metallized dyestuff used in EX- ample 46.

The resulting metallized dye is orange.

Example 56A The orange brown premetallized azo dyestuff of the formula may be prepared as follows. The dyestufi has more than 40 hours light fastness when applied tocotton in medium depth shade, which is surprising and unexpected for azo dyes having pendant thiosulfate groups.

1 g.m.w. of the non-metallized azo dyestuff of Example 43B above is dissolved in 10 liters water, 281.1 'gms. CoSO -7H 'O dissolved in 3 liters water is added thereto, the pH is adjusted to 6.7 with soda ash, the mixture is heated to C. and held at that temperature for 6 hours, while maintaining pH 6.5-7 with soda ash or acetic acid as required. Cool to 45 C., and the dyestutf precipitates on addition of NaCl.

Example 56B be prepared by substituting the copper sulphate solution described in Example 44 above for the C050 solution The scarlet Premetalhzed azo dyestufi of the formula used above, and'lowering the metallization temperature .9 to 65 c. CzHr 9 O 5 The 1:1 iron complex analog of the above dye, may be I prepared by substituting 162.21 gms. FeCl dissolved in @NHSOa-@N=NC=O\ 3 liters water for the C080 solution used above.

7 Example 56D OHrC=N Th 1 2 11' d d f h f 1 may b6 prepared as follows e premeta ize azo ye o t e ormu a OCH OH: C=N\ I @NHSOz@N=N-C=fl 1 g.m.w. of the non-metallized azo dyestufi of Example I 430 is dissolved in 10 liters water, and 594.32 gms. of a may be prepared by the process described in Example aqueous Solution of ifhrolnium acetate m y 56A above, except that the amount of C080 solution 18 added thereto. The pH is ad usted to 6 9 W1th soda ash used in Example 56A i d d b one-1 1i A brown or acetic acid as required. The mixture 1s heated to 9 5 dyestuff resulw C. overnight to insure completion of metallization, while E x a m le 56E maintaining the pH at 6.8-7. The dyestuff precipitates on p adding NaCl. The 1:2 chromium complex compound of the azo dye Exa ple 560 of Example 43C above may be prepared in the same The yellow brown Premetauized azo d t fl f the manner as described in Example 56B above, except that formula cH,-0=N

/N@SSOaNa (])C2H5 III=NC-- may be prepared as follows. i

1 g.m.w. of the non-metallized azo dyestutf of Examthe amount of chromium acetate solution used in Exam- P 4313 is dissolved in 15 liters Water, 281-1 ple 56B is reduced by one-half. A scarlet dyestuff results.

CoSO -7H O dissolved in 3 liters water is added thereto,

and the pH is adjusted to 6.7 with soda ash. The mixture Example 56F is healed hQIIIS i11$11r60mP1ti11 of The 1:2 nickel complex compound of the azo dyestuff metalhzation, while maintaining the pH at -7 with soda of Example 431) above, may be prepared by dissolving 1 ash or acetic acid as required The dye precipitates g.m.w. of the dye of 43D in 10 liters water, adding 131.42

salting with NaCl. I

Th S d t if h r th 40 h ht gms. N1SO -6H Qd1ssolved 1n 3 liters water, ad usting to 6 re u mg yes u as mo e an ours lg pH 6.5, and heating 6-8 hours at 95 C. while mainfastness and excellent wash fastness when applied to cotton in medium depth shade, which is surprising for dyes 6O talnlng P The Orange Premetanlzed dyestuif P- of this type. arates on salting with NaCl.

The 1:1 nickel complex analog of the above dye may Example 57 be prepared by substituting 262.85 gms. NiSO -6H O dissolved in 3 liters water for the C050 solution used above.

The dyestulr' of the formula The 1:1 copper complex analog of the above dye may V may be prepared as follows.

1 g.m.w. of salicylic acid is coupled with 1 g.m.w. f diazotized p-nitroaniline, and the result reduced with 2.1 g.m.w. Na s to form COOH and 1 g.m.w. thereof is diazotized at C. and the diazo coupled with 1 g.m.w. of

to form a non-metallized dyestuff.

The non-metallized dyestuff is dissolved in 10 liters water at 50 C., and a slight excess over 1 g.m.w. CuSO -5H O, dissolved in 1 liter of Water, and 300 gms. sodium acetate are added thereto. The composition is heated to 60 C. for 1 hour; the brown metallized dye precipitates and may be recovered by filtration.

Example 57A The 1:1 cobalt analog of the metallized dyestuif of Example 57 above may be prepared by metallizing 1 g.rn.w. of the non-metallized dyestuif of Example 57 by the metallization method described in Example above, except that the heating to metallize is at 95 C. instead of 80 C.

Example 57B The 1:1 chromium analog of the metallized dyestuif of Example 57 above may be prepared by metallizing 1 g.m.w. of the non-metallized dyestuff of Example 57 by the metallization method described in Example 46 above, except that the heating to metallize is at 95 C. instead of 80 C.

Example 57C The 1:1 nickel analog of the metallized dyestuff of EX- ample 57 above may be prepared by metallizing 1 g.m.w. of the non-metallized dyestuff of Example 57 by the metallization method described in Example 47 above.

Example 57D The 1:1 iron analog of the metallized dyestuif of Example 57 above may be prepared by metallizing 1 g.m.w. of the non-metallized dyestufif of Example 57 by the metallizing method described in Example 50 above.

Example 57E The non-metallized azo dyestuff of the formula may be prepared by tetrazotizing 1 g.m.w. of

6H OH in conventional manner with water, muriatic acid and sodium nitrite at 0 C.; and coupling the resulting aqueous tetrazo with 2 g.m.w. of the product of Example 27 above by adding the tetrazo to an aqueous solution of the prod-v uct of Example 27 at 0 C. and stirring overnight to complete the coupling. The non-metallized dyestuif precipitates on addition of NaCl, and is collected by filtration.

36 Example 57F The non-metallized azo dyestufl? of the formula I OH NBOaS may be prepared by diazotizing 1 g.m.w. of 4-chl0r-2- aminophenol-6-sulfonic acid and coupling the resulting diazo solution with an aqueous solution of 1 g.m.w. of the product of Example 27 adjusted to pH 7 with soda ash, commencing the coupling reaction at 0 C. and stirring overnight While permitting the temperature to rise to 2025 C. The dyestufi precipitates on addition of NaCl, and is collected by filtration.

Example 57G The scarlet premetallized azo dyestulf of the formula NaO3SS @N\ l o @eomnommay be prepared as follows.

1 g.m.w. of the non-metallized dyestuff of Example 57E above and 2 g.m.w. of the dyestuff of Example 57F are stirred into 20 liters water. 1188.64 gms. of a 50% aqueous solution of chromium acetate monohydrate is added; the pH is adjusted to 6.5 with NaOH; following which the aqueous composition is heated at 95 C. for 6 hours, while the pH is maintained at 6.06.5 with NaOH. The product is cooled to 50 C., NaCl is added to precipitate it, following which it is collected by filtration.

Example 57H The cobalt analog of the metallized azo dye of Example 57G may be prepared in the same manner as described in Example 57G, except that 562.2 gms. CoSO '7H O dissolved in 6 liters water is substituted for the chromium acetate solution. The resulting dye is scarlet.

Example 571 The nickel analog of the metallized azo dye of Example 57G above may be prepared in the same manner as described in Example 57G, except that 535.70 gms.

NiSO 6H O dissolved in 6 liters water is substituted for the chromium acetate solution, and except that the heating is at C. A scarlet dyestulf results.

Example v The orange metallized azo dyestulf of the formula 38 Example 58 The azo dyestufr of the formula Example 59 The azo dyestufi of the formula may be prepared in the same manner as described in Example 571 above, except that 2 g.m.w.

COONa CH:C=N is substituted for the dye of Example 57F which is used in Example 571.

The azo dyestuffs of the present invention may also be prepared by coupling a molecular proportion of a tetrazotized bis(diaryldiamine) with two molecular proportions of a pyrazolone compound of the formula to produce a pyrazolone compound of the formula OH OH Y I I may be prepared by coupling 1 g.m.'W. of tetrazotized benzidine with 2 g.rn.w. of

O The coupling may effected as described in Example 58,

and the salt then converted to acid by adding HCl until acid to Congo paper.

The resulting dyestufi is orange.

Example 60 The azo dyestufi of the formula (agent: WN=N C=JJ\ t l L=N SSOaK may be prepared by coupling 1 g.m.w. of tetrazotized 55 4,4-diam-ino-l,1-dinaph-thyl with 2 g.m.w, of

I C a HC=C\ I SSOaK wherein D is an arylene group, such as phenylene, substituted phenylene, naphthylene, or substituted naphthylene, and X, Y, and Z are as above defined and the S50 2 groups are meta or para with respect to the pyrazolonyl groups, that is meta or para with respect to the N attached to the benzene nucleus to which the SSO Z group in question is attached. Several examples follow.

70 The coupling may be effected as described in Example 58,

except that an equivalent amount of KHCO is substituted for the NazHCO used in Example 58. The resulting dyestufi is orange.

39 40 Example 61 Example 64 The azo dyestuif of the formula The azo dyestuff of the formula c1 01 OH I J=CN=N O O N=N-C=(IJ I NH4OaSS@N I I N@SSOaNH4 OH OH may be prepared by coupling 1 g.m.w. of tetrazotized may be prepared by coupling 1 g.m.w. of diazotized p- 4,4-diamin-o2,2'-dichloro-1,1'-dinaphthyl with 2 g.m.w. nitroaniline to 1 g.m.w. of l-phenyl-3-methyl-5-pyrazoof 20 lone, reducing the nitro group of the resulting product to 011 an amine With 210 gms. of a 40% aqueous solution of I sodium sulfhydrate, diazotizing the amine, and coupling l g.m.w. of the resulting diazo compound with l g.m.w.

/ of the product of Example 27 by adding the diazo solu- CH3O C=N 25 tion at C. to a solution of the pyrazolone at 5 C.

The coupling y b6 effected as deSCribed in Example containing 300 gms. sodium bicarbonate to neutralize the eXcept that an equivalent amount of NH4HC'O3 acid liberated during coupling, and holding at C. for

stituted for the NaHCO used in Example 58.

24 hours. The resultm" dyestufi 1S The resulting dyestuff is scarlet.

Example 62 The thiosulfate salt dyes of the present invention may Th 310 dye -tuif f th formula be applied to cotton fabric by padding onto the fabric at may be prepared by coupling 1 g.m.w. of tetrazotized Y P y with 2 of 140 F. a dye solution consisting of 20 parts dye, 100

OH parts thiourea, 2 parts sodium alginate migration inhibi- HC=(IJ tor, and 878 parts Water; squeezing to 60% wet pick up based on fabric weight; pre-drying to 10% moisture con- I tent; and heating in a curing oven at 400 F. for 1 minute a o: to fix the dye. The coupling may be effected as described in Exam le 58 The thiosulfuric acid form dyes of the present invention The resulting dyestufi is reddish orange may be used to dye wool by the commonly known method of applylng acld dyes to wool. Valuable Wet fast dyelngs Example 63 l The azo dyestutf of the formula N=C-CH3 CHaC=N NaOaSS SSOaNa may be prepared as follows. What is claimed is:

Thls example 15 the safne a5 PI 62 Y xcept 1. A dyestulf selected from the group consisting of: that 1 g.m.w. of tetrazotized 4,4-d1am1no-3,3'-d1methoxydiphenyl is substituted for the tetrazotized 4,4'-dia mino- (a) 2,2'-dimethyldiphenyl of Example 63, and except that 65 2 g.m.w. of

It so NH HC=C I a I or; Y

/N CH3C=N I /N I SSOaNa X--C==N SSOaZ are substituted for the pyrazolone intermediate used in Example 62.

The resulting dyestufi is red. 

1. A DYESTUFF SELECTED FROM THE GROUP CONSISTING OF: 